US9870097B2 - Noise cancellation technique for capacitive touchscreen controller using differential sensing - Google Patents
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Abstract
Description
This application is a continuation of U.S. patent application Ser. No. 13/934,496, filed Jul. 3, 2013, and titled “NOISE CANCELLATION TECHNIQUE FOR CAPACITIVE TOUCHSCREEN CONTROLLER USING DIFFERENTIAL SENSING”, which is a continuation of U.S. patent application Ser. No. 12/986,881, filed Jan. 7, 2011, and titled “NOISE CANCELLATION TECHNIQUE FOR CAPACITIVE TOUCHSCREEN CONTROLLER USING DIFFERENTIAL SENSING”, and claims priority under 35 U.S.C. §119(e) of provisional patent application Ser. No. 61/326,830, filed Apr. 22, 2010, and titled “Differential Capacitive Touchpad Circuit and Method,” the disclosures of which are hereby incorporated by reference in their entirety.
The following co-owned patent applications, U.S. patent application Ser. No. 12/986,776, titled “Method and Apparatus for Improving Dynamic Range of a Touchscreen Controller”, U.S. patent application Ser. No. 12/986,841, titled “Charge Transfer Scheme to Convert Capacitance to Voltage for Touchscreen Controller”; U.S. patent application Ser. No. 12/986,841, titled “System Integration of Tactile Feedback and Touchscreen Controller for Near-Zero Latency Haptics Playout”; U.S. patent application Ser. No. 12/987,008, titled “Use of Random Sampling Technique to Reduce Finger-Coupled Noise”; and U.S. patent application Ser. No. 12/986,905 titled “Method and Apparatus for Generating Piezoelectric Transducer Excitation Waveforms Using A Boost Converter”, are all also incorporated by reference in their entireties.
The present invention relates to the field of capacitive sensor arrays. More particularly, the present invention relates to the field of reducing or eliminating errors in the output of capacitive sensor arrays such as touchscreens.
Many electrical devices are incorporating touchscreen type displays. A touchscreen is a display that detects the presence, location, and pressure of a touch within the display area, generally by a finger, hand, stylus, or other pointing device. The touchscreen enables a user to interact with the display panel directly without requiring any intermediate device, rather than indirectly with a mouse or touchpad. Touchscreens can be implemented in computers or as terminals to access networks. Touchscreens are commonly found in point-of-sale systems, automated teller machines (ATMs), mobile phones, personal digital assistants (PDAs), portable game consoles, satellite navigation devices, and information appliances.
There are a number of types of touchscreen technologies. A capacitive touchscreen panel is coated, partially coated, or patterned with a material that conducts a continuous electrical current across a touch sensor. The touch sensor exhibits a precisely controlled field of stored electrons in both the horizontal and vertical axes to achieve capacitance. The human body is also an electrical device that has stored electrons and therefore also exhibits capacitance. When a reference capacitance of the touch sensor is altered by another capacitance field, such as a finger, electronic circuits located at each corner of the panel measure the resultant distortion in the reference capacitance. The measured information related to the touch event is sent to the controller for mathematical processing. Capacitive sensors can either be touched with a bare finger or with a conductive device being held by a bare hand. Capacitive sensors also work based on proximity, and do not have to be directly touched to be triggered. In most cases, direct contact to a conductive metal surface does not occur and the conductive sensor is separated from the user's body by an insulating glass or plastic layer. Devices with capacitive buttons intended to be touched by a finger can often be triggered by quickly waving the palm of the hand close to the surface without touching.
In capacitive touch applications, the touch sensor acts as an antenna that can pick up ambient noise, such as RF and power supply noise. When used in a touchscreen application, the touch sensors are placed on top of a display screen, such as a liquid crystal display (LCD). Switching noise from the LCD adds significant noise to the touch sensors. When used in an application having an RF transceiver, such as a mobile cell phone, additional noise is picked up by the touch sensors. These noises, if not handled correctly, may cause a capacitive touch screen controller (CTSC) to detect false touches and report wrong touched coordinates.
A differential sensing scheme provides a means for detecting one or more touch events on a touch sensitive device in the presence of incident noise. Instead of sensing one touch sensitive channel, such as a row, column, or single touch sensor, multiple touch sensitive channels are sampled at a time. By sampling two nearby channels simultaneously and doing the measurement differentially, noise common to both channels is cancelled. The differential sensing scheme is implemented using simple switch-capacitor analog front-end (AFE) circuitry. The originally sensed data on each individual channel is recovered free of common-mode noise. The recovered sensed data is used to determine the presence of one or more touch events and if present the location of each touch event on the touch sensitive device.
In one aspect, a method of detecting one or more touch events on a touch sensitive device is disclosed. The method includes receiving a plurality of channels, each channel having sensed data corresponding to the touch sensitive device; measuring a capacitance of each channel when no touch event is present on any of the plurality of channels, thereby determining a no touch baseline value for each channel; selecting one of the plurality of channels as a primary channel; selecting another of the plurality of channels as a references channel, wherein the reference channel is different than the primary channel; measuring a capacitance of the primary channel; measuring a capacitance of the reference channel; calculating a difference between the measured capacitance of the primary channel and the measured capacitance of the reference channel, thereby determining a measured difference; calculating a difference between the no touch baseline value for the primary channel and the no touch baseline value for the reference channel, thereby determining a baseline difference; calculating a difference between the measured difference and the baseline difference, thereby determining a delta from baseline for the primary channel and reference channel pair; repeating the steps of selecting one of the plurality of channels as a primary channel, selecting another of the plurality of channels as a reference channel, measuring a capacitance of the primary channel, measuring a capacitance of the reference channel, calculating a difference between the measured capacitance of the primary channel and the measured capacitance of the reference channel, and calculating a difference between the no touch baseline value for the primary channel and the no touch baseline value for the reference channel, for each channel in the plurality of channels so that each channel is selected as the primary channel; and determining one or more touch events from the delta from baselines calculated for all primary channel and reference channel pairs.
In some embodiments, the capacitance of the primary channel and the capacitance of the reference channel are measured simultaneously. In some embodiments, each channel is configured having a same shape and size. In some embodiments, each channel is a row sensor in the touch sensitive device or a column sensor in the touch sensitive device. In some embodiments, the touch sensitive device is a two-dimensional touch panel or a one-dimensional virtual slider. The primary channel and the reference channel each have common-mode noise that is removed in the delta from baseline. In some embodiments, the primary channel and the reference channel are adjacent channels. In some embodiments, selecting the primary channel and the reference channel includes enabling the primary channel and the reference channel. In some embodiments, the method also includes recovering the sensed data from the primary channel and the reference channel after calculating the delta from baseline for the primary channel and reference channel pair. In some embodiments, recovering the sensed data includes performing an integration backwards on the delta from baselines calculated for all primary channel and reference channel pairs, wherein the delta from baselines are sequentially calculated forward starting from a first channel to a last channel, and the integration backwards starts from a last delta from baseline calculated to a first delta from baseline. In some embodiments, the method also includes determining a minimum delta from baseline from the delta from baselines determined for all primary channel and reference channel pairs. In some embodiments, the method also includes calculating adjusted sensed data for each channel by subtracting the minimum delta from baseline from the recovered sensed data for each channel. In some embodiments, common mode noise present in the sensed data is not present in the adjusted sensed data. In some embodiments, determining one or more touch events includes determining multiple touch events.
In yet another aspect, another method of detecting one or more touch events on a touch sensitive device is disclosed. The method includes receiving a plurality of channels, each channel having sensed data corresponding to the touch panel; determining a capacitance of each channel when no touch event is present on any of the plurality of channels, thereby determining a no touch baseline value for each channel; selecting two of the plurality of channels and calculating a difference between the no touch baseline value for the two channels, thereby determining a baseline difference; measuring a capacitance of each of the selected two channels; calculating a difference between the measured capacitances of the two channels, thereby determining a measured difference where a common-mode noise present in both of the selectively measured two channel is removed; calculating a difference between the measured difference and the baseline difference, thereby determining a delta from baseline for the two channels; repeating the steps of selecting two of the plurality of channels and calculating a difference between the no touch baseline value for the two channels, measuring a capacitance of each of the selected two channels, calculating a difference between the measured capacitances of the two channels, and calculating a difference between the measured difference and the baseline difference, for additional channel pairs in the plurality of channels; recovering the sensed data from all the delta from baselines for the channel pairs, wherein the recovered sensed data does not include common-mode noise present in the sensed data; and determining one or more touch events from the recovered sensed data.
In yet another aspect, another method of detecting one or more touch events on a touch panel is disclosed. The method includes receiving a plurality of channels, each channel having sensed data corresponding to the touch panel; determining a capacitance of each channel when no touch event is present on any of the plurality of channels, thereby determining a no touch baseline value for each channel; selecting N of the plurality of channels and calculating a difference between the no touch baseline value for the N channels, thereby determining a baseline difference; measuring a capacitance of each of the selected N channels; calculating a difference between the measured capacitances of the N channels, thereby determining a measured difference where a common-mode noise present in the selectively measured N channels is removed; calculating a difference between the measured difference and the baseline difference, thereby determining a delta from baseline for the N channels; repeating the steps of selecting N of the plurality of channels and calculating a difference between the no touch baseline value for the N channels, measuring a capacitance of each of the selected N channels, calculating a difference between the measured capacitances of the N channels, thereby determining a measured difference where a common-mode noise present in the selectively measured N channels is removed, and calculating a difference between the measured difference and the baseline difference, for additional channel sets in the plurality of channels; recovering the sensed data from all the delta from baselines for the channel sets, wherein the recovered sensed data does not include common-mode noise present in the sensed data; and determining one or more touch events from the recovered sensed data.
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the differential sensing scheme and, together with the description, serve to explain the principles of the haptic feedback system, but not limit the invention to the disclosed examples.
Embodiments of the present invention are directed to a differential sensing scheme. Those of ordinary skill in the art will realize that the following detailed description of the present invention is illustrative only and is not intended to be in any way limiting. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure.
Reference will now be made in detail to implementations of the present invention as illustrated in the accompanying drawings. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts. In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will, of course, be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions must be made in order to achieve the developer's specific goals, such as compliance with application and business related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure.
While the differential sensing scheme will be described in conjunction with the embodiments below, it will be understood that they are not intended to limit the methods and systems of these embodiments and examples. On the contrary, the differential sensing scheme is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the differential sensing scheme as defined by the appended claims. Furthermore, in the following detailed description, numerous specific details are set forth in order to more fully illustrate the methods and systems. However, it will be apparent to one of ordinary skill in the prior art that the methods and systems may be practiced without these specific details.
In accordance with the present application, some of the components, process steps, and/or data structures may be implemented using various types of processing systems, including hardware, software, or any combination thereof. In addition, those of ordinary skill in the art will recognize that devices of a less general purpose nature, such as hardwired devices, application specific integrated circuits (ASICs), or the like, may also be used without departing from the scope and spirit of the inventive concepts disclosed herein.
A differential sensing scheme includes techniques for reducing or eliminating errors in the output of capacitive sensor arrays such as touchpads, touchscreens, touch sliders and the like, including touch sensors that detect the presence and position of a stylus, as well as those that detect and determine finger position. The differential sensing scheme describes a means of extracting a touch event related signal in the presence of extraneous signals. While the illustrative embodiment described herein is applied in a mobile telephone, it is understood that capacitive touch sensors are used in a wide variety of devices. Examples of such devices include, but are not limited to, portable devices, such as personal digital assistants (PDAs), global positioning systems (GPS) receivers, as well as larger devices such as touchscreen enabled displays and computer systems, as well as appliances.
Each touch sensor in the touchpad measures a change in capacitance. The touchpad circuit 20 converts the sensed capacitance change to a voltage. Noise present in the system can alter the change in capacitance perceived by the capacitive touch sensors, making it indistinguishable from a real touch event. Since the capacitive touch sensors are typically placed right on top of a LCD screen, switching noise from the LCD can cause the touchpad circuit 20 to report false touches.
In the differential sensing scheme, the capacitance of two or more channels such as two or more rows/columns of a two-dimensional touch sensor array or two or more elements of a one-dimensional touch sensor array, such as a slider, are measured simultaneously, either directly, or by measuring a voltage present on the elements. The measurements are subtracted to yield a measurement free of common-mode error that is primarily due to incident noise, such as that produced by operation of the LCD, the radio circuits 18, any backlight or other power supply under integrated LCD/touchpad 12 and other external environmental sources of noise. All sources that contribute incident noise, or common-mode noise, sensed at a touch sensor are collectively referred to as “noise sources.”
When a finger or a conductive stylus approaches the touch panel, at the area where the touch panel is contacted, the touch sensor capacitance changes, or in the case of the two-dimensional arrays of touch sensors in
The differential sensing scheme provides a means for detecting a touch event in the presence of incident noise. Instead of sensing one touch sensor/row at a time, multiple touch sensors/rows are sampled at a time. The incident noise is often coupled to the touch sensors with similar if not the same strength. This is especially true for touch sensors that are of the same shape and size and placed in close proximity to each other. By sampling two nearby touch sensors/rows simultaneously and doing the measurement differentially, noise common to both touch sensors/rows is cancelled. The differential sensing scheme is implemented using simple switch-capacitor AFE circuitry. Unlike conventional capacitive sensing schemes, no external RC component or complex analog filtering is required in the differential sensing scheme to filter out the noise.
A control logic circuit 22 provides a reset signal ‘rst’ for resetting AFE1 and AFE2 circuits, which prepares AFE1 and AFE2 circuits to make capacitance measurements. In some embodiments, the control logic 22 is under the control of system host processor, such as the microprocessor 14 in mobile telephone 10 of
In some embodiments, the touchpad circuit 20 and the AFE1 and AFE2 circuits are configured as capacitance measuring circuits. In other embodiments, the touchpad circuit is alternatively configured so that the differential sensing scheme can be used with voltage measuring type capacitive sensor arrangements. Referring now to
The control logic circuit 22 provides a reset signal reset for resetting integrators INTI and INT2. Integrators INT1 and INT2 are reset while selection values sel1 and sel2 are set at address inputs of the multiplexers 26A and 26B for selecting the measurement element voltage and reference element voltage provided to integrators INTI and INT2, respectively. Reset signal reset is de-asserted, permitting integrators INTI and INT2 to integrate the voltages present on the respective selected touchpad elements 28. Another multiplexer 26C is provided for selecting between the outputs of the integrators INTI and INT2, according to a selection signal ‘sel’ provided by control logic 22. The selected output is received as the input of the ADC 24, which provides digital values corresponding to the output voltages of integrators INT1 and INT2 at the end of a measurement interval, after a sample control signal is asserted for sampling the outputs of integrators INT1 and INT2.
Referring again to
In some embodiments of the differential sensing scheme, two channels are sampled at the same time. A first channel is the channel under measurement, referred to as a primary channel, and the output of the first channel is connected to the positive input of the ADC. The output of the second channel, referred to as a reference channel, is connected to the negative input of the ADC. The ADC converts these two inputs differentially to a digital code. The differential sensing scheme operates most effectively if the reference channel has the extraneous incident noise present as a common mode signal. For optimum performance, the two differential channels should be identical in shape and size and physically positioned as close to each other as possible. For this reason, the neighboring channel is preferably chosen as the reference channel since it has the maximum probability of picking-up the same noise as the first channel being measured. For example, when sampling the row 1, row 2 is selected as reference channel and for row 2, row 3 as reference and so on. For eight rows only seven conversions are done. The last row is not sampled. Similarly for column 1, column 2 is the preferred reference channel and for column 2, column 3 is the preferred reference and so on. The last column is not sampled.
Similarly, the “Touched Differential Measurement” line, labeled as step S5, shows results that are the step S3 results adjusted using the step S3 results from the reference row measurement. In other words, the step S5 results are calculated by subtracting the step S3 results of the reference row from the step S3 of the measured row. For example, the value 190 in step S5 for row 1 (measured row) is determined by subtracting the value 1910 in step S3 for row 2 (reference row) from the value 2100 in step S3 for row 1. The “Delta from Baseline” line, labeled as step S6, shows results that are the differences between the No Touch Differential (baseline) row values in step S4 and the Touched Differential Measurement row values in step S5. For example, the value −10 in step S6 for row 1 is calculated by subtracting the value 190 in step S5 for row 1 from the value 200 in step S4 for row 1.
The “Cumulative Sum” line, labeled as step S7, shows the cumulative sum of delta change for each row starting from the last row, row 8. The cumulative sum is defined as the sum of delta change for the present row and the cumulative sum of the previous row. For example, the cumulative sum for row 3 is the delta change for row 3, shown in step S6 for row 3, plus the cumulative sum for row 4. As applied to the values in
In the delta from baseline, row 3 shows an increase in the ADC code as the “Assumed Code Change due to TOUCH” from row 3 to row 4 is maximum. Row 2 shows the maximum negative change from the baseline because the “Assumed Code Change due to TOUCH” from row 2 to row 3 is most negative. The remaining channels, row 4 to row 8, do not show any delta change since the neighboring channels also show zero delta change from baseline. The last row, row 8, is not sampled hence the delta change is zero.
The preceding example was applied to rows of touch sensors. This technique is also applied to columns of touch sensors, the results of which are combined with the results from the row analysis to determine the row and column position of the touch event on the touch panel. This process is well known in the art.
In general, depending on the layout of the sensors, the touch can be present on one or more sensors. Here it is assumed that the touch covers two or more sensors, specifically two sensors for the first touch and three sensors for the second touch. The algorithm also works if the touch covers one or more sensors. The same applies to one touch applications.
The differential sensing scheme is described above in the context of a two-dimensional array of touch sensors, such as the touch panel of
The one-dimensional touch sensor array can be applied to any array having two or more sensors. In the case of a two sensor array, such as the two sensor slider shown in
In an exemplary application, the differential sensing scheme was implemented using parts from Maxim Integrated Products, Inc.™. When a touch panel was put on top of a LCD screen and a single ended sensing scheme was applied, the resulting performance was noisy and many false touches were detected.
As described above, the differential sensing scheme is applied as an adjacent channel implementation, meaning that immediately adjacent touch sensors, row, or columns are used for the differential measurements. Alternatively, the differential sensing scheme can be expanded to include differential comparisons between non-adjacent touch sensors, rows, or columns. For example, row 1 and row 3, row 2 and row 4, row 3 and row 5, and so on can be compared. As another example, row 1 and row 4, row 2 and row 5, row 3 and row 6, and so on can be compared.
As described above, the differential sensing scheme is applied to two sensors, rows, or columns, for example determining the difference between row 1 and row 2. Alternatively, the differential sensing scheme can be applied to more than two sensors, row, or columns.
The present invention has been described in terms of specific embodiments incorporating details to facilitate the understanding of the principles of construction and operation of the invention. Such references, herein, to specific embodiments and details thereof are not intended to limit the scope of the claims appended hereto. It will be apparent to those skilled in the art that modifications can be made in the embodiments chosen for illustration without departing from the spirit and scope of the invention.
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DE (1) | DE102011017231A1 (en) |
TW (2) | TWI562052B (en) |
Families Citing this family (87)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9372576B2 (en) | 2008-01-04 | 2016-06-21 | Apple Inc. | Image jaggedness filter for determining whether to perform baseline calculations |
US8922521B2 (en) | 2009-02-02 | 2014-12-30 | Apple Inc. | Switching circuitry for touch sensitive display |
US8593410B2 (en) | 2009-04-10 | 2013-11-26 | Apple Inc. | Touch sensor panel design |
US8957874B2 (en) | 2009-06-29 | 2015-02-17 | Apple Inc. | Touch sensor panel design |
US8493356B2 (en) | 2010-04-22 | 2013-07-23 | Maxim Integrated Products, Inc. | Noise cancellation technique for capacitive touchscreen controller using differential sensing |
US8599167B2 (en) | 2010-04-22 | 2013-12-03 | Maxim Integrated Products, Inc. | Method and apparatus for improving dynamic range of a touchscreen controller |
US9391607B2 (en) | 2010-04-22 | 2016-07-12 | Qualcomm Technologies, Inc. | Use of random sampling technique to reduce finger-coupled noise |
CN102411447B (en) * | 2010-09-23 | 2014-01-08 | 群康科技(深圳)有限公司 | Input detection device, input detection method, input detection program, and computer readable media |
US8854319B1 (en) | 2011-01-07 | 2014-10-07 | Maxim Integrated Products, Inc. | Method and apparatus for generating piezoelectric transducer excitation waveforms using a boost converter |
TWI433451B (en) * | 2011-02-10 | 2014-04-01 | Raydium Semiconductor Corp | Touch sensing apparatus |
TW201243679A (en) * | 2011-04-25 | 2012-11-01 | Focaltech Systems Ltd | Methods for filtering noise in capacitive touch panel |
US9857921B2 (en) * | 2011-05-13 | 2018-01-02 | Synaptics Incorporated | Input signal correction architecture |
US20120313890A1 (en) * | 2011-06-09 | 2012-12-13 | Maxim Integrated Products, Inc. | Inter-symbol interfence reduction for touch panel systems |
US10795448B2 (en) * | 2011-09-29 | 2020-10-06 | Magic Leap, Inc. | Tactile glove for human-computer interaction |
US9246486B2 (en) | 2011-12-16 | 2016-01-26 | Apple Inc. | Electronic device with noise-cancelling force sensor |
US9753577B2 (en) * | 2011-12-30 | 2017-09-05 | Parade Technologies, Ltd. | Methods and apparatus to perform a detection operation |
KR101941507B1 (en) | 2012-02-10 | 2019-04-12 | 삼성전자주식회사 | Apparatus and method for compensating touch error in electronic device with touch screen |
TWI464637B (en) * | 2012-02-17 | 2014-12-11 | Elan Microelectronics Corp | Dynamic adjusting method of adc transferring parameter of touch panel |
CN103324365A (en) * | 2012-03-20 | 2013-09-25 | 富泰华工业(深圳)有限公司 | Capacitive touch system, touch device and touch method |
US20130265242A1 (en) * | 2012-04-09 | 2013-10-10 | Peter W. Richards | Touch sensor common mode noise recovery |
US9329723B2 (en) * | 2012-04-16 | 2016-05-03 | Apple Inc. | Reconstruction of original touch image from differential touch image |
TWI469007B (en) * | 2012-04-17 | 2015-01-11 | Raydium Semiconductor Corp | Method of controlling noise processing circuit of touch panel and related signal processing device |
KR101931077B1 (en) * | 2012-04-25 | 2018-12-20 | 주식회사 실리콘웍스 | Touch screen Readout circuit removing a noise |
KR101931078B1 (en) * | 2012-04-25 | 2018-12-20 | 주식회사 실리콘웍스 | Method for removing a touch screen panel noise and touch screen readout circuit |
US20130300690A1 (en) * | 2012-04-25 | 2013-11-14 | Silicon Works Co., Ltd. | Control circuit of touch screen and noise removing method |
KR101339581B1 (en) * | 2012-05-30 | 2013-12-10 | 삼성전기주식회사 | Touch sensing apparatus and data processing method thereof |
CN102750060B (en) * | 2012-06-04 | 2015-06-10 | 天津昌立微电子技术有限公司 | Projection-type capacitive touch screen system time domain noise reduction method by space differentiation |
EP2901255B1 (en) * | 2012-07-05 | 2017-10-25 | Cambridge Touch Technologies, Ltd. | Pressure sensing display device |
TWI460632B (en) * | 2012-08-21 | 2014-11-11 | Au Optronics Corp | Method for detecting touch points |
CN104769536B (en) * | 2012-09-17 | 2017-07-18 | 硅工厂股份有限公司 | Control circuit and noise remove method for touch screen |
KR101388699B1 (en) * | 2012-11-22 | 2014-04-24 | 삼성전기주식회사 | Method and apparatus for sensing touch input |
JP6025528B2 (en) | 2012-11-29 | 2016-11-16 | 三菱電機株式会社 | Touch panel device |
US10067575B2 (en) * | 2012-11-30 | 2018-09-04 | Apple Inc. | Noise correction for stylus applications on tablets and other touch devices |
US9354698B2 (en) * | 2012-11-30 | 2016-05-31 | Google Technology Holdings LLC | Differential proximity sensing and side detection for an electronic device |
KR101700842B1 (en) | 2012-12-07 | 2017-02-01 | 엘지디스플레이 주식회사 | Display Device and Method for touch sencing of the same |
TWI480788B (en) * | 2012-12-07 | 2015-04-11 | Tera Xtal Technology Corp | Touch sensing device and method |
US9323353B1 (en) | 2013-01-15 | 2016-04-26 | American Megatrends, Inc. | Capacitance sensing device for detecting a three-dimensional location of an object |
US9110547B1 (en) | 2013-01-15 | 2015-08-18 | American Megatrends Inc. | Capacitance sensing device |
US8717325B1 (en) | 2013-02-18 | 2014-05-06 | Atmel Corporation | Detecting presence of an object in the vicinity of a touch interface of a device |
CN103135875A (en) * | 2013-03-01 | 2013-06-05 | 昆山工研院新型平板显示技术中心有限公司 | Sensor sensing based AMOLED (active matrix organic light emitting diode) touch display screen |
CN103257743A (en) * | 2013-03-05 | 2013-08-21 | 昆山工研院新型平板显示技术中心有限公司 | AMOLED (active matrix/organic light emitting diode) display screen with touch sensor |
KR101514533B1 (en) * | 2013-07-29 | 2015-04-22 | 삼성전기주식회사 | Touch sensing apparatus and method capable of supporting hover sensing |
US9886141B2 (en) | 2013-08-16 | 2018-02-06 | Apple Inc. | Mutual and self capacitance touch measurements in touch panel |
KR101416724B1 (en) * | 2013-10-15 | 2014-07-09 | 주식회사 아나패스 | Method for Removing Common Noise and Touch Information Sensing Method using the same |
KR20150058712A (en) * | 2013-11-20 | 2015-05-29 | 삼성전자주식회사 | Touch Screen Controller generating single-ended touch signal, Touch Screen System and Operating Method thereof |
US9886142B2 (en) * | 2013-12-03 | 2018-02-06 | Pixart Imaging Inc. | Capacitive touch sensing system |
CN104699294B (en) | 2013-12-04 | 2017-12-08 | 禾瑞亚科技股份有限公司 | The arrangement for detecting of touch trajectory, system and method |
CN109117023A (en) * | 2013-12-05 | 2019-01-01 | 禾瑞亚科技股份有限公司 | Exclude the method and apparatus of line segment group corresponding to palm |
KR102112528B1 (en) * | 2013-12-10 | 2020-05-19 | 엘지디스플레이 주식회사 | Display device and method of driving the same |
JP2015122020A (en) * | 2013-12-25 | 2015-07-02 | シナプティクス・ディスプレイ・デバイス合同会社 | Touch panel control circuit and semiconductor integrated circuit including the same |
CA2937700A1 (en) | 2014-01-22 | 2015-07-30 | Tactual Labs Co. | Dynamic assignment of possible channels in a touch sensor |
JP6446055B2 (en) | 2014-02-18 | 2018-12-26 | ケンブリッジ タッチ テクノロジーズ リミテッドCambridge Touch Technologies Limited | Power mode dynamic switching for touch screen with force touch |
US9354734B2 (en) * | 2014-03-04 | 2016-05-31 | Atmel Corporation | Common-mode hover detection |
JP6552869B2 (en) | 2014-05-02 | 2019-07-31 | 株式会社半導体エネルギー研究所 | Information processing device |
US10289251B2 (en) | 2014-06-27 | 2019-05-14 | Apple Inc. | Reducing floating ground effects in pixelated self-capacitance touch screens |
KR20160011849A (en) * | 2014-07-23 | 2016-02-02 | 주식회사 실리콘웍스 | Touch panel sensing apparatus and controlling apparatus thereof |
US10429998B2 (en) * | 2014-07-23 | 2019-10-01 | Cypress Semiconductor Corporation | Generating a baseline compensation signal based on a capacitive circuit |
US9746974B2 (en) * | 2014-08-21 | 2017-08-29 | Cypress Semiconductor Corporation | Providing a baseline capacitance for a capacitance sensing channel |
US9880655B2 (en) | 2014-09-02 | 2018-01-30 | Apple Inc. | Method of disambiguating water from a finger touch on a touch sensor panel |
EP3175330A4 (en) | 2014-09-22 | 2017-08-30 | Apple Inc. | Ungrounded user signal compensation for pixelated self-capacitance touch sensor panel |
US9772725B2 (en) | 2014-09-24 | 2017-09-26 | Synaptics Incorporated | Hybrid sensing to reduce latency |
US10712867B2 (en) | 2014-10-27 | 2020-07-14 | Apple Inc. | Pixelated self-capacitance water rejection |
US9563319B2 (en) | 2014-12-18 | 2017-02-07 | Synaptics Incorporated | Capacitive sensing without a baseline |
GB2533667B (en) | 2014-12-23 | 2017-07-19 | Cambridge Touch Tech Ltd | Pressure-sensitive touch panel |
US10318038B2 (en) | 2014-12-23 | 2019-06-11 | Cambridge Touch Technologies Ltd. | Pressure-sensitive touch panel |
CN107209602B (en) | 2015-02-02 | 2020-05-26 | 苹果公司 | Flexible self-capacitance and mutual capacitance touch sensing system architecture |
KR101645668B1 (en) | 2015-02-13 | 2016-08-05 | 주식회사 하이딥 | Capacitance measuring circuit and touch input device including the same |
US10488992B2 (en) | 2015-03-10 | 2019-11-26 | Apple Inc. | Multi-chip touch architecture for scalability |
CN105147316B (en) * | 2015-09-11 | 2020-05-05 | 深圳市理邦精密仪器股份有限公司 | Common mode noise suppression method using channel data processing |
US10365773B2 (en) | 2015-09-30 | 2019-07-30 | Apple Inc. | Flexible scan plan using coarse mutual capacitance and fully-guarded measurements |
GB2544307B (en) | 2015-11-12 | 2018-02-07 | Cambridge Touch Tech Ltd | Processing signals from a touchscreen panel |
US10282046B2 (en) | 2015-12-23 | 2019-05-07 | Cambridge Touch Technologies Ltd. | Pressure-sensitive touch panel |
GB2544353B (en) | 2015-12-23 | 2018-02-21 | Cambridge Touch Tech Ltd | Pressure-sensitive touch panel |
GB2547031B (en) | 2016-02-05 | 2019-09-25 | Cambridge Touch Tech Ltd | Touchscreen panel signal processing |
CN107102210B (en) * | 2016-02-22 | 2019-08-30 | 深圳市汇顶科技股份有限公司 | A kind of capacitance determining method and device based on capacitive touch chip |
US9817535B2 (en) * | 2016-03-07 | 2017-11-14 | Synaptics Incorporated | Mitigating spatially correlated noise in data from capacitive sensors |
TWI588726B (en) * | 2016-03-21 | 2017-06-21 | 財團法人工業技術研究院 | Reading circuit for capacitive sensor and operation method thereof |
US10095363B2 (en) | 2016-03-28 | 2018-10-09 | Synaptics Incorporated | Capacitive sensing with high pass filtering for segmentation |
US10365749B2 (en) | 2016-03-30 | 2019-07-30 | Synaptics Incorporated | Capacitive sensing device with single reference channel |
CN107315450A (en) * | 2016-04-26 | 2017-11-03 | 世意法(北京)半导体研发有限责任公司 | Touch screen controller for determining the relation between the hand of user and the housing of electronic equipment |
AU2017208277B2 (en) | 2016-09-06 | 2018-12-20 | Apple Inc. | Back of cover touch sensors |
KR20180072042A (en) * | 2016-12-20 | 2018-06-29 | 엘지디스플레이 주식회사 | Touch circuit, touch sensing device, and touch sensing method |
US10386965B2 (en) | 2017-04-20 | 2019-08-20 | Apple Inc. | Finger tracking in wet environment |
CN107357473A (en) * | 2017-05-18 | 2017-11-17 | 华显光电技术(惠州)有限公司 | Capacitance plate touch-control adjustment method |
GB2565305A (en) | 2017-08-08 | 2019-02-13 | Cambridge Touch Tech Ltd | Device for processing signals from a pressure-sensing touch panel |
US10466842B2 (en) | 2017-09-12 | 2019-11-05 | Cypress Semiconductor Corporation | Suppressing noise in touch panels using a shield layer |
EP3547088A4 (en) * | 2017-12-27 | 2019-12-25 | Shenzhen Goodix Technology Co., Ltd. | Noise detection method and device, electronic apparatus, and computer readable storage medium |
Citations (105)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4277784A (en) | 1979-07-13 | 1981-07-07 | Commodore Electronics Limited | Switch scanning means for use with integrated circuits |
US4477834A (en) | 1981-05-29 | 1984-10-16 | The Marconi Company Limited | Scan conversion circuit |
US4527096A (en) | 1984-02-08 | 1985-07-02 | Timex Corporation | Drive circuit for capacitive electroluminescent panels |
US5168153A (en) | 1990-11-01 | 1992-12-01 | Fuji Xerox Co., Ltd. | Integrator and image read device |
US5313141A (en) | 1993-04-22 | 1994-05-17 | Durel Corporation | Three terminal inverter for electroluminescent lamps |
US5444459A (en) | 1990-12-03 | 1995-08-22 | Zeelan Technology, Inc. | Signal acquisition system utilizing ultra-wide time range time base |
US5463388A (en) | 1993-01-29 | 1995-10-31 | At&T Ipm Corp. | Computer mouse or keyboard input device utilizing capacitive sensors |
US5463283A (en) | 1994-05-24 | 1995-10-31 | Bkl, Inc. | Drive circuit for electroluminescent lamp |
WO1997043825A1 (en) | 1996-05-15 | 1997-11-20 | Analog Devices, Inc. (Adi) | Fully differential voltage controlled operational transconductance amplifier |
US5789870A (en) | 1996-05-06 | 1998-08-04 | Durel Corporation | Low noise inverter for EL lamp |
CN1189719A (en) | 1996-11-15 | 1998-08-05 | 阿尔卑斯电气株式会社 | Weak current monitoring circuit and coordinate input device of utilizing the same |
US20020011991A1 (en) | 2000-07-25 | 2002-01-31 | Mitsuharu Iwasaki | Circuit for generating touch detection signals, locator device and a method of generating touch detection signals |
US6466036B1 (en) | 1998-11-25 | 2002-10-15 | Harald Philipp | Charge transfer capacitance measurement circuit |
US20020149561A1 (en) | 2000-08-08 | 2002-10-17 | Masaaki Fukumoto | Electronic apparatus vibration generator, vibratory informing method and method for controlling information |
US20030067449A1 (en) | 2001-10-10 | 2003-04-10 | Smk Corporation | Touch panel input device |
US20030174121A1 (en) | 2002-01-28 | 2003-09-18 | Sony Corporation | Mobile apparatus having tactile feedback function |
WO2004040240A1 (en) | 2002-10-31 | 2004-05-13 | Harald Philipp | Charge transfer capacitive position sensor |
US6744426B1 (en) | 1999-08-10 | 2004-06-01 | Brother Kogyo Kabushiki Kaisha | Pen coordinate reading device with pen attribute detecting function |
US6847354B2 (en) | 2000-03-23 | 2005-01-25 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Three dimensional interactive display |
US20050073202A1 (en) | 2003-03-25 | 2005-04-07 | Gasperi Michael Lee | Method and apparatus for determining a switching signal state |
WO2005050612A2 (en) | 2003-11-19 | 2005-06-02 | Koninklijke Philips Electronics N. V. | Circuit arrangement for driving a display arrangement |
US6937124B1 (en) | 2004-02-13 | 2005-08-30 | Fujitsu Component Limited | Plane plate vibration device and switch employing the same |
US20060064626A1 (en) | 2004-09-22 | 2006-03-23 | Kencast, Inc. | System, method and apparatus for FEC encoding and decoding |
US20060092177A1 (en) | 2004-10-30 | 2006-05-04 | Gabor Blasko | Input method and apparatus using tactile guidance and bi-directional segmented stroke |
US20060097991A1 (en) | 2004-05-06 | 2006-05-11 | Apple Computer, Inc. | Multipoint touchscreen |
US20060119586A1 (en) | 2004-10-08 | 2006-06-08 | Immersion Corporation, A Delaware Corporation | Haptic feedback for button and scrolling action simulation in touch input devices |
US7061327B2 (en) | 2002-01-24 | 2006-06-13 | Maxim Integrated Products, Inc. | Single supply headphone driver/charge pump combination |
US20060221061A1 (en) | 2005-03-31 | 2006-10-05 | Tyco Electronic Corporation | Touch sensor and control with random pulse spacing |
TWI271645B (en) | 2005-04-19 | 2007-01-21 | Elan Microelectronics Corp | Capacitive touchpad with a physical key function |
US7176753B2 (en) | 2004-01-23 | 2007-02-13 | Ricoh Company, Ltd. | Method and apparatus for outputting constant voltage |
TW200712997A (en) | 2005-09-23 | 2007-04-01 | Elan Microelectronics Corp | Method for compensating sensitivity of touch pad sensor |
US20070074913A1 (en) | 2005-10-05 | 2007-04-05 | Geaghan Bernard O | Capacitive touch sensor with independently adjustable sense channels |
US20070080951A1 (en) | 2002-08-29 | 2007-04-12 | Sony Corporation | Input device and electronic device using the input device |
US7283120B2 (en) | 2004-01-16 | 2007-10-16 | Immersion Corporation | Method and apparatus for providing haptic feedback having a position-based component and a predetermined time-based component |
US20070268272A1 (en) | 2006-05-19 | 2007-11-22 | N-Trig Ltd. | Variable capacitor array |
WO2007146780A2 (en) | 2006-06-09 | 2007-12-21 | Apple Inc. | Touch screen liquid crystal display |
US20080007247A1 (en) | 2006-06-13 | 2008-01-10 | Itron, Inc. | Filtering techniques to remove noise from a periodic signal and Irms calculations |
US20080041640A1 (en) | 1992-06-08 | 2008-02-21 | Synaptics Incorporated | Object position detector with edge motion feature and gesture recognition |
US20080055277A1 (en) | 2006-08-29 | 2008-03-06 | Sony Corporation | Touch panel display, electronic apparatus and playing apparatus |
US20080062145A1 (en) | 2000-01-19 | 2008-03-13 | Immersion Corporation | Haptic interface for touch screen embodiments |
US20080062147A1 (en) | 2006-06-09 | 2008-03-13 | Hotelling Steve P | Touch screen liquid crystal display |
US20080061139A1 (en) | 2006-09-07 | 2008-03-13 | Ncr Corporation | Self-checkout terminal including scale with remote reset |
US20080127739A1 (en) | 2006-02-10 | 2008-06-05 | Deangelis Alfred R | Capacitive sensor |
US20080143313A1 (en) | 2006-12-18 | 2008-06-19 | Tang Zong-Hong | Adjusting method and device of sensitivity of signal interpretation |
US20080158169A1 (en) | 2007-01-03 | 2008-07-03 | Apple Computer, Inc. | Noise detection in multi-touch sensors |
US20080158176A1 (en) | 2007-01-03 | 2008-07-03 | Apple Computer, Inc. | Full scale calibration measurement for multi-touch surfaces |
US20080158180A1 (en) | 2007-01-03 | 2008-07-03 | Apple Inc. | Scan sequence generator |
US20080161946A1 (en) | 2006-12-28 | 2008-07-03 | Kabushiki Kaisha Toshiba | Method and system for monitoring apparatus |
US20080158182A1 (en) | 2007-01-03 | 2008-07-03 | Apple Inc. | Periodic sensor panel baseline adjustment |
US20080162997A1 (en) | 2007-01-03 | 2008-07-03 | Apple Inc. | Channel scan logic |
US20080162996A1 (en) | 2007-01-03 | 2008-07-03 | Apple, Inc. | Multi-touch auto scanning |
US20080309627A1 (en) | 2007-06-13 | 2008-12-18 | Apple Inc. | Integrated in-plane switching |
US20090009486A1 (en) | 2007-07-03 | 2009-01-08 | Hitachi Displays, Ltd. | Display device with touch panel |
TW200905538A (en) | 2007-07-31 | 2009-02-01 | Elan Microelectronics Corp | Touch position detector of capacitive touch panel and method of detecting the touch position |
US20090055580A1 (en) | 2007-08-21 | 2009-02-26 | Microsoft Corporation | Multi-level dram controller to manage access to dram |
US20090096890A1 (en) | 2007-10-16 | 2009-04-16 | Micron Technology, Inc. | Method and apparatus for controlling dual conversion gain signal in imaging devices |
TW200917130A (en) | 2007-10-02 | 2009-04-16 | Tontek Design Technology Ltd | Method of current source for control and compensation touch sensing capacitor detector and apparatus thereof |
WO2009061044A1 (en) | 2007-11-07 | 2009-05-14 | Atlab Inc. | Touch panel device and method of detecting contact position thereof |
US20090127003A1 (en) * | 2007-11-21 | 2009-05-21 | Geaghan Bernard O | System and Method for Determining Touch Positions Based on Position-Dependent Electrical Charges |
US20090153152A1 (en) | 2007-12-14 | 2009-06-18 | Cypress Semiconductor Corporation | Compensation circuit for a tx-rx capacitive sensor |
US20090167704A1 (en) | 2007-12-31 | 2009-07-02 | Apple Inc. | Multi-touch display screen with localized tactile feedback |
US20090167326A1 (en) | 2007-12-28 | 2009-07-02 | Geaghan Bernard O | Time-sloped capacitance measuring circuits and methods |
US20090174416A1 (en) | 2005-06-03 | 2009-07-09 | Synaptics Incorporated | Methods and systems for detecting a capacitance using switched charge transfer techniques |
US20090198907A1 (en) | 2008-02-01 | 2009-08-06 | Speight William E | Dynamic Adjustment of Prefetch Stream Priority |
TWM363639U (en) | 2007-06-13 | 2009-08-21 | Apple Inc | Apparatus and system for obtaining a plurality of values from a touch sensor panel, computing system, mobile telephone, and digital audio player |
US20090284495A1 (en) | 2008-05-14 | 2009-11-19 | 3M Innovative Properties Company | Systems and methods for assessing locations of multiple touch inputs |
CN101634924A (en) | 2009-08-25 | 2010-01-27 | 友达光电股份有限公司 | Touch panel device with high touch sensitivity and touch positioning method thereof |
TW201008118A (en) | 2008-04-10 | 2010-02-16 | Atmel Corp | Capacitive touch screen with noise suppression |
US7667371B2 (en) | 2007-09-17 | 2010-02-23 | Motorola, Inc. | Electronic device and circuit for providing tactile feedback |
TW201011620A (en) | 2008-09-08 | 2010-03-16 | Tpo Displays Corp | Sensing circuit for capacitive touch panel |
CN101673155A (en) | 2008-09-10 | 2010-03-17 | 苹果公司 | single-chip multi-stimulus sensor controller |
US20100073323A1 (en) | 2008-09-24 | 2010-03-25 | Geaghan Bernard O | Mutual capacitance measuring circuits and methods |
US20100079383A1 (en) | 2008-09-26 | 2010-04-01 | Suggs Bradley N | Distributing touch data |
TW201015412A (en) | 2008-10-15 | 2010-04-16 | Ene Technology Inc | A method for automatically adjusting capacitance baseline of touch button |
CN101714036A (en) | 2008-10-08 | 2010-05-26 | 禾瑞亚科技股份有限公司 | Touch method and device for distinguishing true touch |
WO2010065207A1 (en) | 2008-12-05 | 2010-06-10 | Maxim Integrated Products, Inc | Audio amplifier apparatus driving a panel to produce both audio signal and haptic feedback |
US20100144391A1 (en) | 2008-12-05 | 2010-06-10 | Shih Chang Chang | Integrated touch panel for a TFT display |
US20100156818A1 (en) | 2008-12-23 | 2010-06-24 | Apple Inc. | Multi touch with multi haptics |
US20100156823A1 (en) | 2008-12-23 | 2010-06-24 | Research In Motion Limited | Electronic device including touch-sensitive display and method of controlling same to provide tactile feedback |
US20100214259A1 (en) | 2007-07-31 | 2010-08-26 | Harald Philipp | Sensor and method of sensing |
CN101840293A (en) | 2010-01-21 | 2010-09-22 | 宸鸿科技(厦门)有限公司 | Scanning method for projected capacitive touch panels |
US20100245286A1 (en) | 2009-03-25 | 2010-09-30 | Parker Tabitha | Touch screen finger tracking algorithm |
US20100277351A1 (en) | 2007-12-13 | 2010-11-04 | Taylor John P | Capacitive sensing user interfaces and implementation thereof |
US20100302198A1 (en) | 2007-08-13 | 2010-12-02 | Nuvoton Technology Corporation | Power Efficient Capacitive Detection |
US20100308838A1 (en) | 2009-06-04 | 2010-12-09 | Samsung Electro-Mechanics Co., Ltd. | Electronic apparatus transmitting and receiving signal through single wire |
US20110025629A1 (en) | 2009-07-28 | 2011-02-03 | Cypress Semiconductor Corporation | Dynamic Mode Switching for Fast Touch Response |
US20110037705A1 (en) | 2009-08-11 | 2011-02-17 | Atmel Corporation | Touch-sensitive user interface |
US20110061949A1 (en) | 2009-09-11 | 2011-03-17 | Christoph Horst Krah | Measuring body capacitance effect in touch sensitive device |
US20110084936A1 (en) | 2009-10-09 | 2011-04-14 | Egalax_Empia Technology Inc. | Method and device for capacitive position detection |
US20110128250A1 (en) | 2009-12-02 | 2011-06-02 | Murphy Mark J | Method and device for detecting user input |
US20110157069A1 (en) | 2009-12-31 | 2011-06-30 | Zhiming Zhuang | Electronic device and method for determining a touch input applied to a capacitive touch panel system incorporated therein |
US20110157438A1 (en) | 2009-12-31 | 2011-06-30 | Compton John T | Pausing column readout in image sensors |
US20110156839A1 (en) | 2009-12-31 | 2011-06-30 | Silicon Laboratories Inc. | Capacitive sensor with variable corner frequency filter |
US20110248931A1 (en) | 2010-04-08 | 2011-10-13 | Research In Motion Limited | Tactile feedback for touch-sensitive display |
US20110248930A1 (en) | 2010-04-08 | 2011-10-13 | Research In Motion Limited | Portable electronic device and method of controlling same to provide tactile feedback |
US20110261005A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | Method and apparatus for improving dynamic range of a touchscreen controller |
US20110260990A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | System integration of tactile feedback and touchscreen controller for near-zero latency haptics playout |
US20110261008A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | Use of random sampling technique to reduce finger-coupled noise |
US20110261006A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | System for and method of transferring charge to convert capacitance to voltage for touchscreen controllers |
US20110261007A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | Noise cancellation technique for capacitive touchscreen controller using differential sensing |
US8054299B2 (en) | 2007-01-08 | 2011-11-08 | Apple Inc. | Digital controller for a true multi-point touch surface useable in a computer system |
US20120043976A1 (en) | 2006-03-31 | 2012-02-23 | Bokma Louis W | Touch detection techniques for capacitive touch sense systems |
US20120050213A1 (en) | 2010-08-27 | 2012-03-01 | Bokma Louis W | Reduced noise capacitive scan |
US20120113047A1 (en) * | 2010-04-30 | 2012-05-10 | Microchip Technology Incorporated | Capacitive touch system using both self and mutual capacitance |
US8576189B1 (en) | 2010-08-24 | 2013-11-05 | Cypress Semiconductor Corp. | AC line synchronization for capacitive sensing |
-
2011
- 2011-01-07 US US12/986,881 patent/US8493356B2/en active Active
- 2011-03-24 TW TW105103379A patent/TWI562052B/en active
- 2011-03-24 TW TW100110112A patent/TWI530848B/en not_active IP Right Cessation
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-
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- 2013-07-03 US US13/934,496 patent/US9442610B2/en active Active
-
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- 2016-06-30 US US15/199,757 patent/US9870097B2/en active Active
Patent Citations (120)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4277784A (en) | 1979-07-13 | 1981-07-07 | Commodore Electronics Limited | Switch scanning means for use with integrated circuits |
US4477834A (en) | 1981-05-29 | 1984-10-16 | The Marconi Company Limited | Scan conversion circuit |
US4527096A (en) | 1984-02-08 | 1985-07-02 | Timex Corporation | Drive circuit for capacitive electroluminescent panels |
US5168153A (en) | 1990-11-01 | 1992-12-01 | Fuji Xerox Co., Ltd. | Integrator and image read device |
US5444459A (en) | 1990-12-03 | 1995-08-22 | Zeelan Technology, Inc. | Signal acquisition system utilizing ultra-wide time range time base |
US20080041640A1 (en) | 1992-06-08 | 2008-02-21 | Synaptics Incorporated | Object position detector with edge motion feature and gesture recognition |
US5463388A (en) | 1993-01-29 | 1995-10-31 | At&T Ipm Corp. | Computer mouse or keyboard input device utilizing capacitive sensors |
US5313141A (en) | 1993-04-22 | 1994-05-17 | Durel Corporation | Three terminal inverter for electroluminescent lamps |
US5463283A (en) | 1994-05-24 | 1995-10-31 | Bkl, Inc. | Drive circuit for electroluminescent lamp |
US5789870A (en) | 1996-05-06 | 1998-08-04 | Durel Corporation | Low noise inverter for EL lamp |
WO1997043825A1 (en) | 1996-05-15 | 1997-11-20 | Analog Devices, Inc. (Adi) | Fully differential voltage controlled operational transconductance amplifier |
CN1189719A (en) | 1996-11-15 | 1998-08-05 | 阿尔卑斯电气株式会社 | Weak current monitoring circuit and coordinate input device of utilizing the same |
US6075520A (en) | 1996-11-15 | 2000-06-13 | Rohm Co., Ltd. | Small current detector circuit and locator device using the same |
US6466036B1 (en) | 1998-11-25 | 2002-10-15 | Harald Philipp | Charge transfer capacitance measurement circuit |
US6744426B1 (en) | 1999-08-10 | 2004-06-01 | Brother Kogyo Kabushiki Kaisha | Pen coordinate reading device with pen attribute detecting function |
US20080062145A1 (en) | 2000-01-19 | 2008-03-13 | Immersion Corporation | Haptic interface for touch screen embodiments |
US6847354B2 (en) | 2000-03-23 | 2005-01-25 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Three dimensional interactive display |
US20020011991A1 (en) | 2000-07-25 | 2002-01-31 | Mitsuharu Iwasaki | Circuit for generating touch detection signals, locator device and a method of generating touch detection signals |
US20020149561A1 (en) | 2000-08-08 | 2002-10-17 | Masaaki Fukumoto | Electronic apparatus vibration generator, vibratory informing method and method for controlling information |
US20030067449A1 (en) | 2001-10-10 | 2003-04-10 | Smk Corporation | Touch panel input device |
US7061327B2 (en) | 2002-01-24 | 2006-06-13 | Maxim Integrated Products, Inc. | Single supply headphone driver/charge pump combination |
US20030174121A1 (en) | 2002-01-28 | 2003-09-18 | Sony Corporation | Mobile apparatus having tactile feedback function |
US20070080951A1 (en) | 2002-08-29 | 2007-04-12 | Sony Corporation | Input device and electronic device using the input device |
WO2004040240A1 (en) | 2002-10-31 | 2004-05-13 | Harald Philipp | Charge transfer capacitive position sensor |
US20050073202A1 (en) | 2003-03-25 | 2005-04-07 | Gasperi Michael Lee | Method and apparatus for determining a switching signal state |
WO2005050612A2 (en) | 2003-11-19 | 2005-06-02 | Koninklijke Philips Electronics N. V. | Circuit arrangement for driving a display arrangement |
US7283120B2 (en) | 2004-01-16 | 2007-10-16 | Immersion Corporation | Method and apparatus for providing haptic feedback having a position-based component and a predetermined time-based component |
US7176753B2 (en) | 2004-01-23 | 2007-02-13 | Ricoh Company, Ltd. | Method and apparatus for outputting constant voltage |
US6937124B1 (en) | 2004-02-13 | 2005-08-30 | Fujitsu Component Limited | Plane plate vibration device and switch employing the same |
US20060097991A1 (en) | 2004-05-06 | 2006-05-11 | Apple Computer, Inc. | Multipoint touchscreen |
CN1942853B (en) | 2004-05-06 | 2011-06-08 | 苹果公司 | Touch screen with transparent capacity sensing medium and related display device and computing system |
US20060064626A1 (en) | 2004-09-22 | 2006-03-23 | Kencast, Inc. | System, method and apparatus for FEC encoding and decoding |
US20060119586A1 (en) | 2004-10-08 | 2006-06-08 | Immersion Corporation, A Delaware Corporation | Haptic feedback for button and scrolling action simulation in touch input devices |
US20060092177A1 (en) | 2004-10-30 | 2006-05-04 | Gabor Blasko | Input method and apparatus using tactile guidance and bi-directional segmented stroke |
US20060221061A1 (en) | 2005-03-31 | 2006-10-05 | Tyco Electronic Corporation | Touch sensor and control with random pulse spacing |
TWI271645B (en) | 2005-04-19 | 2007-01-21 | Elan Microelectronics Corp | Capacitive touchpad with a physical key function |
US20090174416A1 (en) | 2005-06-03 | 2009-07-09 | Synaptics Incorporated | Methods and systems for detecting a capacitance using switched charge transfer techniques |
TW200712997A (en) | 2005-09-23 | 2007-04-01 | Elan Microelectronics Corp | Method for compensating sensitivity of touch pad sensor |
US20070074913A1 (en) | 2005-10-05 | 2007-04-05 | Geaghan Bernard O | Capacitive touch sensor with independently adjustable sense channels |
US20080127739A1 (en) | 2006-02-10 | 2008-06-05 | Deangelis Alfred R | Capacitive sensor |
US20120043976A1 (en) | 2006-03-31 | 2012-02-23 | Bokma Louis W | Touch detection techniques for capacitive touch sense systems |
US20070268272A1 (en) | 2006-05-19 | 2007-11-22 | N-Trig Ltd. | Variable capacitor array |
US20080062147A1 (en) | 2006-06-09 | 2008-03-13 | Hotelling Steve P | Touch screen liquid crystal display |
WO2007146780A2 (en) | 2006-06-09 | 2007-12-21 | Apple Inc. | Touch screen liquid crystal display |
US20080007247A1 (en) | 2006-06-13 | 2008-01-10 | Itron, Inc. | Filtering techniques to remove noise from a periodic signal and Irms calculations |
US20080055277A1 (en) | 2006-08-29 | 2008-03-06 | Sony Corporation | Touch panel display, electronic apparatus and playing apparatus |
US20080061139A1 (en) | 2006-09-07 | 2008-03-13 | Ncr Corporation | Self-checkout terminal including scale with remote reset |
US20080143313A1 (en) | 2006-12-18 | 2008-06-19 | Tang Zong-Hong | Adjusting method and device of sensitivity of signal interpretation |
US20080161946A1 (en) | 2006-12-28 | 2008-07-03 | Kabushiki Kaisha Toshiba | Method and system for monitoring apparatus |
US20080158169A1 (en) | 2007-01-03 | 2008-07-03 | Apple Computer, Inc. | Noise detection in multi-touch sensors |
US20080158182A1 (en) | 2007-01-03 | 2008-07-03 | Apple Inc. | Periodic sensor panel baseline adjustment |
US20080162997A1 (en) | 2007-01-03 | 2008-07-03 | Apple Inc. | Channel scan logic |
US20080158176A1 (en) | 2007-01-03 | 2008-07-03 | Apple Computer, Inc. | Full scale calibration measurement for multi-touch surfaces |
US20080158180A1 (en) | 2007-01-03 | 2008-07-03 | Apple Inc. | Scan sequence generator |
US20080162996A1 (en) | 2007-01-03 | 2008-07-03 | Apple, Inc. | Multi-touch auto scanning |
US20100188356A1 (en) | 2007-01-03 | 2010-07-29 | Minh-Dieu Thi Vu | Channel scan logic |
US8054299B2 (en) | 2007-01-08 | 2011-11-08 | Apple Inc. | Digital controller for a true multi-point touch surface useable in a computer system |
US20080309627A1 (en) | 2007-06-13 | 2008-12-18 | Apple Inc. | Integrated in-plane switching |
TWM363639U (en) | 2007-06-13 | 2009-08-21 | Apple Inc | Apparatus and system for obtaining a plurality of values from a touch sensor panel, computing system, mobile telephone, and digital audio player |
US20090009486A1 (en) | 2007-07-03 | 2009-01-08 | Hitachi Displays, Ltd. | Display device with touch panel |
TW200905538A (en) | 2007-07-31 | 2009-02-01 | Elan Microelectronics Corp | Touch position detector of capacitive touch panel and method of detecting the touch position |
US20090032312A1 (en) | 2007-07-31 | 2009-02-05 | Chun-Chung Huang | Touch Position Detector of Capacitive Touch Panel and Method for Detecting the Touch Position |
US20100214259A1 (en) | 2007-07-31 | 2010-08-26 | Harald Philipp | Sensor and method of sensing |
US20100302198A1 (en) | 2007-08-13 | 2010-12-02 | Nuvoton Technology Corporation | Power Efficient Capacitive Detection |
US20090055580A1 (en) | 2007-08-21 | 2009-02-26 | Microsoft Corporation | Multi-level dram controller to manage access to dram |
US7667371B2 (en) | 2007-09-17 | 2010-02-23 | Motorola, Inc. | Electronic device and circuit for providing tactile feedback |
TW200917130A (en) | 2007-10-02 | 2009-04-16 | Tontek Design Technology Ltd | Method of current source for control and compensation touch sensing capacitor detector and apparatus thereof |
US20090096890A1 (en) | 2007-10-16 | 2009-04-16 | Micron Technology, Inc. | Method and apparatus for controlling dual conversion gain signal in imaging devices |
WO2009061044A1 (en) | 2007-11-07 | 2009-05-14 | Atlab Inc. | Touch panel device and method of detecting contact position thereof |
TW200921485A (en) | 2007-11-07 | 2009-05-16 | Atlab Inc | Touch panel device and method of detecting contact position thereof |
US20090127003A1 (en) * | 2007-11-21 | 2009-05-21 | Geaghan Bernard O | System and Method for Determining Touch Positions Based on Position-Dependent Electrical Charges |
US20100277351A1 (en) | 2007-12-13 | 2010-11-04 | Taylor John P | Capacitive sensing user interfaces and implementation thereof |
US20090153152A1 (en) | 2007-12-14 | 2009-06-18 | Cypress Semiconductor Corporation | Compensation circuit for a tx-rx capacitive sensor |
US20090167326A1 (en) | 2007-12-28 | 2009-07-02 | Geaghan Bernard O | Time-sloped capacitance measuring circuits and methods |
US20090167704A1 (en) | 2007-12-31 | 2009-07-02 | Apple Inc. | Multi-touch display screen with localized tactile feedback |
US20090198907A1 (en) | 2008-02-01 | 2009-08-06 | Speight William E | Dynamic Adjustment of Prefetch Stream Priority |
TW201008118A (en) | 2008-04-10 | 2010-02-16 | Atmel Corp | Capacitive touch screen with noise suppression |
US20090284495A1 (en) | 2008-05-14 | 2009-11-19 | 3M Innovative Properties Company | Systems and methods for assessing locations of multiple touch inputs |
TW201011620A (en) | 2008-09-08 | 2010-03-16 | Tpo Displays Corp | Sensing circuit for capacitive touch panel |
CN101673155A (en) | 2008-09-10 | 2010-03-17 | 苹果公司 | single-chip multi-stimulus sensor controller |
US20100073323A1 (en) | 2008-09-24 | 2010-03-25 | Geaghan Bernard O | Mutual capacitance measuring circuits and methods |
US20100079383A1 (en) | 2008-09-26 | 2010-04-01 | Suggs Bradley N | Distributing touch data |
CN101714036A (en) | 2008-10-08 | 2010-05-26 | 禾瑞亚科技股份有限公司 | Touch method and device for distinguishing true touch |
TW201015412A (en) | 2008-10-15 | 2010-04-16 | Ene Technology Inc | A method for automatically adjusting capacitance baseline of touch button |
US20100144391A1 (en) | 2008-12-05 | 2010-06-10 | Shih Chang Chang | Integrated touch panel for a TFT display |
US20100141408A1 (en) | 2008-12-05 | 2010-06-10 | Anthony Stephen Doy | Audio amplifier apparatus to drive a panel to produce both an audio signal and haptic feedback |
WO2010065207A1 (en) | 2008-12-05 | 2010-06-10 | Maxim Integrated Products, Inc | Audio amplifier apparatus driving a panel to produce both audio signal and haptic feedback |
US20100156818A1 (en) | 2008-12-23 | 2010-06-24 | Apple Inc. | Multi touch with multi haptics |
US20100156823A1 (en) | 2008-12-23 | 2010-06-24 | Research In Motion Limited | Electronic device including touch-sensitive display and method of controlling same to provide tactile feedback |
US20100245286A1 (en) | 2009-03-25 | 2010-09-30 | Parker Tabitha | Touch screen finger tracking algorithm |
US20100308838A1 (en) | 2009-06-04 | 2010-12-09 | Samsung Electro-Mechanics Co., Ltd. | Electronic apparatus transmitting and receiving signal through single wire |
US20110025629A1 (en) | 2009-07-28 | 2011-02-03 | Cypress Semiconductor Corporation | Dynamic Mode Switching for Fast Touch Response |
US20110037705A1 (en) | 2009-08-11 | 2011-02-17 | Atmel Corporation | Touch-sensitive user interface |
CN101634924A (en) | 2009-08-25 | 2010-01-27 | 友达光电股份有限公司 | Touch panel device with high touch sensitivity and touch positioning method thereof |
US20110061949A1 (en) | 2009-09-11 | 2011-03-17 | Christoph Horst Krah | Measuring body capacitance effect in touch sensitive device |
US20110084936A1 (en) | 2009-10-09 | 2011-04-14 | Egalax_Empia Technology Inc. | Method and device for capacitive position detection |
US20110128250A1 (en) | 2009-12-02 | 2011-06-02 | Murphy Mark J | Method and device for detecting user input |
US20110157438A1 (en) | 2009-12-31 | 2011-06-30 | Compton John T | Pausing column readout in image sensors |
US20110156839A1 (en) | 2009-12-31 | 2011-06-30 | Silicon Laboratories Inc. | Capacitive sensor with variable corner frequency filter |
US20110157069A1 (en) | 2009-12-31 | 2011-06-30 | Zhiming Zhuang | Electronic device and method for determining a touch input applied to a capacitive touch panel system incorporated therein |
US20110175835A1 (en) | 2010-01-21 | 2011-07-21 | Tpk Touch Solutions (Xiamen) Inc | Method for Scanning Projective Capacitive Touch Panel, Storage Medium and Apparatus for Scanning Projective Capacitive Touch Panel |
CN101840293A (en) | 2010-01-21 | 2010-09-22 | 宸鸿科技(厦门)有限公司 | Scanning method for projected capacitive touch panels |
US20110248931A1 (en) | 2010-04-08 | 2011-10-13 | Research In Motion Limited | Tactile feedback for touch-sensitive display |
US20110248930A1 (en) | 2010-04-08 | 2011-10-13 | Research In Motion Limited | Portable electronic device and method of controlling same to provide tactile feedback |
US8599167B2 (en) | 2010-04-22 | 2013-12-03 | Maxim Integrated Products, Inc. | Method and apparatus for improving dynamic range of a touchscreen controller |
US20110261006A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | System for and method of transferring charge to convert capacitance to voltage for touchscreen controllers |
US20110261007A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | Noise cancellation technique for capacitive touchscreen controller using differential sensing |
US20110261008A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | Use of random sampling technique to reduce finger-coupled noise |
US20110261005A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | Method and apparatus for improving dynamic range of a touchscreen controller |
US9442610B2 (en) | 2010-04-22 | 2016-09-13 | Qualcomm Technologies, Inc. | Noise cancellation technique for capacitive touchscreen controller using differential sensing |
US20160209947A1 (en) | 2010-04-22 | 2016-07-21 | Qualcomm Technologies, Inc. | Noise cancellation tecnique for capacitive touchscreen controller using differential sensing |
US8493356B2 (en) | 2010-04-22 | 2013-07-23 | Maxim Integrated Products, Inc. | Noise cancellation technique for capacitive touchscreen controller using differential sensing |
US20110260990A1 (en) | 2010-04-22 | 2011-10-27 | Maxim Integrated Products, Inc. | System integration of tactile feedback and touchscreen controller for near-zero latency haptics playout |
US20160291797A1 (en) | 2010-04-22 | 2016-10-06 | Qualcomm Technologies, Inc. | Use of random sampling technique to reduce finger-coupled noise |
US8624870B2 (en) | 2010-04-22 | 2014-01-07 | Maxim Integrated Products, Inc. | System for and method of transferring charge to convert capacitance to voltage for touchscreen controllers |
US8830207B1 (en) | 2010-04-22 | 2014-09-09 | Maxim Integrated Products, Inc. | Method and apparatus for improving dynamic range of a touchscreen controller |
US9391607B2 (en) | 2010-04-22 | 2016-07-12 | Qualcomm Technologies, Inc. | Use of random sampling technique to reduce finger-coupled noise |
US20120113047A1 (en) * | 2010-04-30 | 2012-05-10 | Microchip Technology Incorporated | Capacitive touch system using both self and mutual capacitance |
US8576189B1 (en) | 2010-08-24 | 2013-11-05 | Cypress Semiconductor Corp. | AC line synchronization for capacitive sensing |
US20120050213A1 (en) | 2010-08-27 | 2012-03-01 | Bokma Louis W | Reduced noise capacitive scan |
Non-Patent Citations (51)
Title |
---|
Carrica et al., (Oct. 2001) "Random Sampling Applied to the Measurement of a DC Signal Immersed in Noise," IEEE Transactions on Instrumentation and Measurement, 50(5): 1319-1323. |
Chinese First Office Action dated Mar. 17, 2015 issued in CN Patent Application No. 201110108196.2. |
Chinese First Office Action dated Mar. 27, 2015 issued in CN Patent Application No. 201110108187.3. |
Chinese First Office Action dated Mar. 27, 2015 issued in CN Patent Application No. 201110108199.6. |
Chinese First Office Action dated Mar. 30, 2015 issued in CN 201110108101.7. |
Chinese Second Office Action dated Aug. 31, 2015 issued in Patent Application No. CN 201110108196.2. |
Chinese Second Office Action dated Dec. 11, 2015 issued in Patent Application No. CN 201110108187.3. |
Chinese Third Office Action dated Apr. 27, 2016 issued in Patent Application No. CN 201110108187.3. |
German Office Action dated Jun. 8, 2017 issued in Patent Application No. DE 10 2011 017 251.3. |
International Preliminary Report on Patentability and Written Opinion-PCT/US09/61359-ISA/EPO-dated Jun. 11, 2009. |
International Preliminary Report on Patentability and Written Opinion—PCT/US09/61359—ISA/EPO—dated Jun. 11, 2009. |
International Search Report-PCT/US09/61359-ISA/EPO-dated Dec. 3, 2009. |
International Search Report—PCT/US09/61359—ISA/EPO—dated Dec. 3, 2009. |
Radatz, J. The IEEE standard dictionary of electrical terms, (1996) sixth edition, pp. 196-197 and p. 544. |
Taiwan Notice of Allowance and Search Report dated Oct. 28, 2016 issued in Patent Application No. TW 105113167. |
Taiwan Notice of Allowance dated Jul. 29, 2016 issued in Patent Application No. TW 105103379. |
Taiwan Office Action and Search Report dated Nov. 17, 2015 issued in TW Patent Application No. TW 100110334. |
Taiwan Office Action and Search Report dated Oct. 1, 2015 issued in TW Patent Application No. TW 100109904. |
Taiwan Office Action dated Jun. 11, 2015 issued in TW 100109906. |
Taiwan Office Action dated May 27, 2015 issued in TW 1001101112. |
U.S. App. No. 13/934,496, filed Jul. 3, 2013, Joharapurkar et al. |
U.S. App. No. 15/176,006, filed Jun. 7, 2016, Joharapurkar et al. |
U.S. Final Office Action dated Dec. 1, 2014, issued in U.S. Appl. No. 12/987,008. |
U.S. Final Office Action dated Feb. 5, 2013, issued in U.S. Appl. No. 12/315,690. |
U.S. Final Office Action dated Jul. 20, 2017, issued in U.S. Appl. No. 15/176,006. |
U.S. Final Office Action dated Mar. 18, 2015, issued in U.S. Appl. No. 13/934,496. |
U.S. Final Office Action dated Mar. 27, 2012, issued in U.S. Appl. No. 12/315,690. |
U.S. Final Office Action dated Oct. 2, 2013, issued in U.S. Appl. No. 12/315,690. |
U.S. Final Office Action dated Sep. 23, 2013, issued in U.S. Appl. No. 12/987,008. |
U.S. Final Office Action dated Sep. 24, 2015, issued in U.S. Appl. No. 12/987,008. |
U.S. Notice of Allowance dated Dec. 3, 2015, issued in U.S. Appl. No. 12/987,008. |
U.S. Notice of Allowance dated Jan. 14, 2016, issued in U.S. Appl. No. 13/934,496. |
U.S. Notice of Allowance dated Jul. 10, 2013, issued in U.S. Appl. No. 12/986,776. |
U.S. Notice of Allowance dated Jun. 2, 2015, issued in U.S. Appl. No. 13/934,496. |
U.S. Notice of Allowance dated Mar. 14, 2016, issued in U.S. Appl. No. 12/987,008. |
U.S. Notice of Allowance dated Mar. 25, 2013, issued in U.S. Appl. No. 12/986,881. |
U.S. Notice of Allowance dated May 2, 2014 , issued in U.S. Appl. No. 14/070,955. |
U.S. Notice of Allowance dated May 2, 2016, issued in U.S. Appl. No. 13/934,496. |
U.S. Notice of Allowance dated Sep. 24, 2015, issued in U.S. Appl. No. 13/934,496. |
U.S. Notice of Allowance dated Sep. 4, 2013, issued in U.S. Appl. No. 12/986,841. |
U.S. Office Action dated Apr. 16, 2013, issued in U.S. Appl. No. 12/986,841. |
U.S. Office Action dated Apr. 6, 2015, issued in U.S. Appl. No. 12/987,008. |
U.S. Office Action dated Aug. 29, 2012, issued in U.S. Appl. No. 12/315,690. |
U.S. Office Action dated Feb. 6, 2013, issued in U.S. Appl. No. 12/986,776. |
U.S. Office Action dated Jan. 13, 2014, issued in U.S. Appl. No. 14/070,955. |
U.S. Office Action dated Jun. 20, 2013, issued in U.S. Appl. No. 12/315,690. |
U.S. Office Action dated Jun. 5, 2014, issued in U.S. Appl. No. 12/987,008. |
U.S. Office Action dated Mar. 24, 2017, issued in U.S. Appl. No. 15/176,006. |
U.S. Office Action dated May 23, 2013, issued in U.S. Appl. No. 12/987,008. |
U.S. Office Action dated Nov. 19, 2014, issued in U.S. Appl. No. 13/934,496. |
U.S. Office Action dated Sep. 29, 2011, issued in U.S. Appl. No. 12/315,690. |
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US20160209947A1 (en) | 2016-07-21 |
TW201626197A (en) | 2016-07-16 |
US20160313863A1 (en) | 2016-10-27 |
US8493356B2 (en) | 2013-07-23 |
TWI562052B (en) | 2016-12-11 |
CN102262490A (en) | 2011-11-30 |
TW201203065A (en) | 2012-01-16 |
TWI530848B (en) | 2016-04-21 |
CN102262490B (en) | 2016-01-13 |
DE102011017231A1 (en) | 2012-02-23 |
DE102011017231A8 (en) | 2013-07-11 |
US20110261007A1 (en) | 2011-10-27 |
US9442610B2 (en) | 2016-09-13 |
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